Don't use len(SEQUENCE) as condition value (#7249)

* Don't use len(SEQUENCE) as condition value

* Update volvooncall.py

homeassistant/components/binary_sensor/maxcube.py

@@ -26,7 +26,7 @@ def setup_platform(hass, config, add_devices, discovery_info=None):
         if cube.is_windowshutter(device):
             devices.append(MaxCubeShutter(hass, name, device.rf_address))
 
-    if len(devices):
+    if devices:
         add_devices(devices)